1. Field of the Invention
The present invention relates to a hard disc device, and in particular, to a handheld or portable hard disc device.
2. Description of the Related Art
A portable hard disc device can carry a huge volume of information compared to an optical disc such as a DVD (Digital Versatile Disc), a blue-ray disc, and can read information at high speed. However, the hard disc device is required to have a closed structure together with a disc, a head slider, and an arm unit for moving the head slider, in order to prevent dust from intruding, and the hard disc device has a large number of parts. Therefore, there is high probability that failure may be caused by vibration of a mobile phone or repeated use. Moreover, a large number of parts make it difficult to realize the reduction in size, weight and cost.
JP-A-2003-272367 discloses a potable hard disc device in which a case which accommodates a disc, a head slider, an arm mechanism for holding and moving the head slider, and a circuit unit for controlling the movement of the arm mechanism is accommodated in a housing with a shock absorber interposed between the case and housing. The portable hard disc is electrically connected to an external computer via terminals provided in the housing.
JP-A-2003-196964 discloses an information storage apparatus having a hard disc unit, a rechargeable battery, an electromagnetic-induction recharging unit, and a communication unit. The electromagnetic-induction recharging unit receives power supply from the outside without contact, and recharges the rechargeable battery periodically. Then the rechargeable battery supplies power to the hard disc unit. The communication unit transmits and receives data to and from external apparatuses such as a PC or a mobile phone without electric contact, and mediates transmission or reception of data between the external apparatuses and the hard disc unit.
JP-A-2003-178572 discloses a hard disc unit which is reproduced by a CD changer corresponding to the hard disc unit. The CD changer corresponding to the hard disc unit can reproduce a CD magazine in the same manner as a conventional CD changer and the hard disc unit. The hard disc unit disclosed in JP-A-2003-178572 has almost the same appearance as the CD magazine, and has connectors to be electrically connected to the CD changer corresponding to the hard disc unit.
JP-A-8-306178 discloses a removable disc cartridge and a system body on which the disc cartridge is mounted. The disc cartridge is composed of cases A and B, the case A has a disc and a head slider therein, and the case B has a primary magnetic disc directly connected to a disc supporting pole, a secondary magnetic disc for controlling the location of the head slider therein. In addition, electric signal type connectors for transmitting and receiving data between the disc cartridge and the system body are provided in the cases A and B. A motor for rotating a disc and a voice coil motor type coil motor is arranged at the system body, that is, outside the disc cartridge. The disc cartridge is mounted on the system body, then the disc is rotated after the rotating shaft of the disc rotating motor of the system body is fitted into the primary magnetic disc, and then the location of the head slider is controlled after the voice coil motor type coil motor of the system body is fitted into the second magnetic disc.
JP-A-6-267239 discloses a locking mechanism of a small handheld or portable hard disc device. The locking mechanism fixes a disc by pressing a pad against an outer peripheral end of the disc while the disc is not rotating. The locking mechanism fixes the disc by pressing pads against at least two spots which are hard to be nodes for vibration of the disc.
JP-A-2001-202144 discloses a power unit for supplying power to a hard disc device after receiving power supply from a USB 20. While the power unit regulates power bound for the hard disc device by extracting only the current below 500 mA from the power supply from the USB 20, the power unit recharges an electric double-layer capacitor to a predetermined extent. When the recharging capacitance reaches a predetermined capacitance, the current below 500 mA from the USB 20 and the output current from the electric double-layer capacitor are supplied to the hard disc device, so that the shortage of driving power is covered by using only the output from the USB 20 having a defined power capacitance.
JP-A-2003-157520 discloses a method of forming a disc by nano-imprinting. In the nano-imprinting method, a buffer layer is disposed in a position corresponding to a recessed/projected pattern formation area (information forming area) of the disc, and then the recessed/projected pattern of the disc is transferred to a transfer target substrate.
Since the above-described hard disc device has a large number of components, it is inappropriate for preserving recording information for a long time. Moreover, a large number of parts make it difficult to realize the reduction in size and weight, thus portability should be enhanced. A large number of parts make it difficult to realize in cost as well, thus the cost should be lowered.